Core support is requested for biostatistical assistance to each Project under the overall Program. Biostatistical procedures include the following. 1. Design, randomization, and data analysis of the multi-center clinical trial. 2. Design and data analysis of laboratory assays and studies. 3. Statistical analysis of clinical results and correlation with laboratory assays. 4. Design and maintenance of a computerized data management system, including database design, data entry systems, and data verification processes, and data security. 5. Preparation of data for presentation and publication, including data entry, data verification, data analysis, manuscript writing, and implementation of protocol design.